
union3.o:     file format elf32-littlearm


Disassembly of section .text:

00000000 <main>:
当改变一个联合成员的值时，实际上修改了该联合所有成员的值。

 */

void main()
{
   0:	e92d4800 	push	{fp, lr}
   4:	e28db004 	add	fp, sp, #4
   8:	e24dde65 	sub	sp, sp, #1616	; 0x650
    union u_data var, mydata[100];

    printf("sizeof = %ld = %ld\n", sizeof(var), sizeof(mydata)); // 16, 1600
   c:	e3a02d19 	mov	r2, #1600	; 0x640
  10:	e3a01010 	mov	r1, #16
  14:	e59f0008 	ldr	r0, [pc, #8]	; 24 <main+0x24>
  18:	ebfffffe 	bl	0 <printf>
}
  1c:	e24bd004 	sub	sp, fp, #4
  20:	e8bd8800 	pop	{fp, pc}
  24:	00000000 	.word	0x00000000
